title: Diagnosis of viability in early pregnancy with vaginal sonography.
abstract: The detection rate of embryonic heart action using vaginal sonography was evaluated in 363 normal singleton pregnancies in the first trimester. Visible cardiac activity was present at the earliest at a gestational age of 40 days; in addition, the smallest chorionic cavity had a mean diameter of 9.3 mm, the lowest human chorionic gonadotropin (beta-hCG) concentration (calibrated against the first international reference preparation) measured 6,770 mIU/mL, the thinnest trophoblast was 1 mm, and the shortest crown-rump length was 2 mm. Cardiac pulsations were identified in all cases either at a menstrual age greater than or equal to 46 days, a beta-hCG greater than or equal to 47,171 mIU/mL, a mean chorionic cavity diameter greater than or equal to 18.3 mm, or a trophoblast thickness greater than or equal to 5 mm. The heart rate (mean +/- SD) increased from 110 +/- 8 beats per minute (bpm) at 5 weeks menstrual age to 170 +/- 6 bpm at 9 weeks and declined thereafter to 159 +/- 3 bpm at 13 weeks. Vaginal sonography enables a rapid and reliable assessment of embryonic life in early pregnancy.
authors.affiliation: Department of Obstetrics and Gynecology, University of Würzburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Rempen
mesh_terms: D006063:Chorionic Gonadotropin / Q000097:blood; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy / Q000097:blood; D014327:Trophoblasts / Q000000981:diagnostic imaging; D014463:Ultrasonography
chemical_list: D006063:Chorionic Gonadotropin